4691 1,4-Naphthoquinone 1,4-Naphthoquinone or para-naphthoquinone is an organic compound derived from naphthalene. Several isomeric naphthoquinones are known, notably 1,2-naphthoquinone. 1,4-Naphthoquinone forms volatile yellow triclinic crystals and has a sharp odor similar to benzoquinone. It is almost insoluble in cold water, slightly soluble in petroleum ether, and more soluble in polar organic solvents. In alkaline solutions it produces a reddish-brown color. Vitamin K is a derivative of 1,4-naphthoquinone. It is a planar molecule with one aromatic ring fused to a quinone subunit. Naphthalene is a constituent of jet fuel, diesel fuel and cigarette smoke. It is also a byproduct of incomplete combustion and hence is an ubiquitous environmental pollutant. The typical air concentration of naphthalene in cities is about 0.18 ppb. 130-15-4 8530 C10H6O2 White powder. 126°C No indication of carcinogenicity to humans (not listed by IARC). This is a toxic chemical found in cigarettes or generated by tobacco combustion. 2014-09-08T02:39:04Z 2014-12-24T20:26:54Z C02617 27418 true O=C1C=CC(=O)C2=CC=CC=C12 C10H6O2 InChI=1S/C10H6O2/c11-9-5-6-10(12)8-4-2-1-3-7(8)9/h1-6H InChIKey=FRASJONUBLZVQX-UHFFFAOYSA-N 158.1534 158.036779436 Exogenous Solid CHEMBL55934 8215